Steam-engine.



No. 737,043. PATENTED AUG. 25, 1903;

' J. STUMPP. STEAM ENGINE.

APPLICATION FILED APR. 3, 1903.

10 MODEL.

e e d witneagjjawg 17 Patented August 25, I903.

' PATENT OFF CE.

J OHANN STIIMPF, OF BERLIN, GERMANY.

STEAM-ENGI'N E.

SPECIFICATION forming part of Letters Patent No. 737,043, dated August 25, 1903.

Application filed April 3, 1903. Serial No. 150,945. (No model.)

1'0 ail whom it may concern: v

Be it known that I, J OHANN STUMPF, a subject of the German Emperor, residing at 27 Rankestrasse, Berlin, Germany, have invented certain new and useful Improvements Relating to Stea1n-Turbines,-of which the following is a specification.

In steam-turbines which are provided with relatively large wheels the heat radiation from the'casin g which carries the inlet-orifices indicates a temperature of the rim of the wheel which is considerably higher than the" temperature of the disk or web of the wheel. If the steam introduced into the casing, is of a somewhat high pressure, the rim of the wheel becomes of a temperatureup to 150 and more, as trials have confirmed, while the disk or web of the Wheel has the temperature of the condenser, which is, for example, only about 40 to 50. A further increase of the temperature of the rim of the wheel results from the friction of the steam on the blade. surfaces. The superheating resulting from the wall-friction is transmitted partly to the steam and partly also to the wheel. In order to avoid the disadvantages which result fromv these circumstances, the steam conveying passage is according to the invention provided with a protecting arrangement for preventing the radiation of heat.

. least, in turbines where the blades are mounted uponthe outer periphery of the turbine- Wheel, the steam-conveying passage is in the.

form of an annulus or of an annular casing surrounding the turbine-wheel. According to the invention a protecting arrangement is provided for preventing the radiation of heat from the said surrounding annulus or annular casing; but the invention is of general application to turbines of different type where the steam-conveying passage .is otherwise disposed.

In the drawing the invention is illustrated by a detailed cross-section of the respective parts. I

As illustrated in the drawing, the disk at of the turbine-wheel carries a rim 1?, overhanging on each side. The rim is surrounded by the annular steam-conveying casing or passage c, which will have a very high tempera ture when steam of high pressure is employed.

Generally, or, at-

The high temperature of the steam-conveying-casing or passage effects the heating of the rim b by immediate radiation, from which a substantially higher temperature of the rim results than the temperature of the disk or .web of the wheel, so that the formation of cracks or splits in thelrim may result. In order to protect the wheel against considerable heating, metal sheets d are provided at both'sides of the wheel upon the casing 13.

The metal sheets d are fixed, as illustrated in the drawing, by such means as pins e in such manner that an insulating hollow space is provided between the casing c and the metal sheets. This hollow space may be filled with any material being a bad conductor of heat, such as asbestos or the like.

What I claim as my invention, and desire to secure by Letters Patent, is

, 1. In steam-turbines, a'turbine-wheel, a I

a space between the said metal sheet and the casing, substantially as described.

3. In steam-turbines, a turbinewheel, a steam-conveyin g casing surrounding the rim of said wheel, an insulation between said casing and the rim of said wheel and a free space between said insulation and said rim, substantially as described.

4. In steam-turbines, a turbine wheel, a steam-conveying casing surrounding the rim of said wheel, and an insulation between said casing and the rim of said wheel consisting of metal sheets fixed to the casing leaving an insulating-space between the metal sheet and the casing, substantially as described.

In testimony whereof .I have signed my name to this specification in the presence of two subscribing witnesses.

J OI-IANN STUMPF. 

